This invention relates generally to control mechanisms operable about two or more mutually perpendicular axes for mechanically or electrically transmitting commands for movement in two or more directions. More specifically, this invention relates to an electro-mechanical hand controller comprising two gimbal elements mounted on shafts having mutually perpendicular axes of rotation, each shaft being suitably interconnected to means for generating electrical signals, corresponding to movement of the shafts about their respective axes of rotation, for controlling some dynamic process, such as aircraft flight, air refueling boom control, radar tracking operations, and the like.
Prior art electro-mechanical controllers suffer certain disadvantages limiting their effectiveness for use such as in aircraft control, because of their vibration sensitivity, high hysteresis characteristics and inaccurate and erratic operation near the center (or null) position, relatively large displacement required to provide a suitable signal, and lack of suitability for miniaturization to accommodate the space and weight requirements within an aircraft or the like. Additionally, conventional displacement type hand controllers require undesirably high breakout forces and exhibit high hysteresis and dead-band characteristics. These characteristics contribute to errors making such controllers relatively unsuitable for continuous tracking applications, such as radar tracking, aiming of weapons or sensors, and like processes.
The foregoing problems characteristic of prior art controllers have been eliminated or significantly reduced in critical importance by the invention described herein, providing an improved two-axis electromechanical hand controller for controlling a dynamic process, such as the flight of an aircraft. This invention comprises a control member in the form of a hand grip connected to two gimbal elements having mutually perpendicular axes of rotation, an adjustable spring centering configuration for the two gimbal elements and an adjustable counterweight for accurately restoring the grip to a predetermined reference (null) position when a displacement force is removed, and electrical transducers for sensing the angular positions of the two gimbal elements and transmitting the appropriate signal to the process being controlled.
Accordingly, it is an object of this invention to provide an improved two-axis electromechanical controller.
It is a further object of this invention to provide an improved two-axis electromechanical controller having an adjustable spring centering means and adjustable counterweight for accurately and reliably returning the controller to the null position when a displacement force is removed.
It is still a further object of this invention to provide an improved two-axis electromechanical controller having no breakout force, hysteresis or dead-band characteristics.
These and other objects of the invention will beecome apparent as the description thereof proceeds.